Young Rölf is a character in Zombies in the Snow, a movie directed by Gustav Sebald. Rölf refuses to hide from the zombies behind the oak barriers like the rest of the town folk, instead continuing to build his snowman.
A letter written from Sally Sebald to Lemony Snicket contains a picture of the actor who played the young boy. Sally thinks his name might be "Omar", a name that is often confused with "Olaf" in A Series of Unfortunate Events. However, the film contains a message using the Sebald Code for Dr. Montgomery about the Baudelaire children, which means the film must have been recently filmed and the actor must still be a child and thus not Count Olaf.
In the TV adaption, Gustav portrayed Rölf.